GP, Oxford

• Asthma profiles: Healthcare professionals

Professor of Environmental & Respiratory Medicine Institute of Occupational and Environmental Medicine University of Birmingham

• Asthma profiles: Healthcare professionals

Debbie has been using e-cigarettes for two weeks and has cut down from about twenty cigarettes to five per day. She has also reduced the nicotine strength in the e-cigarette to the weakest dose. Her mother died recently of lung cancer. The money she is saving on cigarettes is helping to pay the mortgage for her holiday home. She plans to give up both smoking cigarettes and e-cigarettes by her next birthday.

Jai has been smoking for about twenty five years. He has used different methods to try to give up smoking like patches, chewing gum - but he always ended up going back to smoking cigarettes. In December 2014 he started using e-cigarettes every day and he has reduced cigarettes from twenty a day to five or ten a week. He said that it is important to find the right flavour that works for you.

In 2009, Anthony decided to explore alternatives to smoking. He smoked about twenty per day and was concerned about his health when he developed a persistent night cough. He has mild asthma. He uses e-cigarettes with pre-filled cartridges. He has reduced the amount of nicotine, but estimates that he vapes the equivalent of twenty cigarettes per day.

Rosanna became curious about e-cigarettes following a visit from one of her sons who was using e-cigarettes to try to give up smoking. Her son showed her online information about e-cigarettes. Rosanna aims to give up smoking cigarettes gradually. At the moment, she is using e-cigarettes to cut down the number of cigarettes she smokes. She no longer feels the need to smoke at work and if needed, she uses her e-cigarette.

Judith, 36, gave up smoking when she was 34. Judith is White Scottish, works as a communications manager and lives by herself. She gave up smoking after being diagnosed with emphysema. Judith started smoking at 14-15. She soon started smoking cannabis to cope with her mental health problems. She always thought she had a smoker's cough' but was later diagnosed with emphysema. It was incredibly hard for Judith to stop smoking, but she managed it with the support of a smoking cessation group.

Tom, 32, gave up smoking when he was 29. Tom is White British, a software consultant and lives with his wife. He smoked for fifteen years before he cut down and then gave up smoking altogether. Tom did not use any stop smoking' aids, and feels his change in attitude and determination to quit were important factors.

Mariam, 36, gave up smoking at the age of 43. Mariam is Asian, lives with her two sons and her mother. She came to England from Kyrgyzstan when she was 30. Mariam started smoking with Russian women at work. She started buying her own and smoked when she was lonely. Later, her son found her cigarettes and persuaded her to give up. She now feels much brighter and healthier.

Andrew, 32, is White British, works as a supermarket manager and lives by himself. He has quit smoking for 18 months. Andrew first started smoking with his friends when he was 16. He smoked 20 a day like clockwork' until he tried to stop. Andrew had previously had a few attempts at quitting smoking with the help of nicotine replacement patches, but has now stopped for 18 months and has since trained for a marathon.